The formation of hydridopentacyanorhodate(III): a reappraisal of the formation of hydridoaquotetracyanorhodate(III)

Abstract

The reaction of NaCN with [Rh(CO)₂Cl]₂ results in the formation of Na₃RhH(CN)₅. The anion has been isolated as the Na, K, Rb, and Cs salts. The ¹H n.m.r., Raman, and i.r. spectra are reported for these compounds, and for the intermediates in the above reaction. Three long-lived solution species have been identified as Rh(CO)₂(CN)Cl^–, trans-Rh(CO)₂(CN)₂^–, and Rh(CO)(CN)₃^2– and the existence of at least two other intermediates may be inferred. The hydride previously formulated as K₂Rh(CN)₄(H)(H₂O) is almost certainly K₃Rh(CN)₅(H),xH₂O.